基于图像处理的矿石颗粒三维微观孔隙结构演化

采用高精度显微CT技术及三维图像分析方法研究氧化铜矿石颗粒在酸浸前后内部微观孔隙结构特征及其演变，考察孔隙率、孔隙尺寸分布、孔隙连通度、孔隙分维等参数的变化规律。结果表明：酸浸后矿石颗粒的孔隙率明显增加，孔隙尺寸分布范围更广，出现一定比例的大孔隙，平均孔隙直径增加2~3倍；孔隙连通度在酸浸前基本为零，酸浸后明显增加，并在各方向上呈现空间变异性；孔隙分维数在浸出结束后也有所增大，且在一定范围内与孔隙率及平均孔隙直径呈指数增长关系。借助三维图像分析可实现矿石浸出过程中内部微观孔隙结构的定量描述，从而揭示矿石颗粒孔隙结构的演化规律。

3 D micropore structure evolution of ore particles based on image processing

The micropore structure and evolution of copper oxide ore particles before and after acid leaching were investigated by high resolution X-ray micro-computed tomography (micro-CT) and three-dimensional (3D) image analysis. The pore structure param-eters, such as porosity, pore size distribution, pore connectivity and fractal dimension were statistically calculated. The results indi-cate that after acid leaching, the porosity increases obviously and the pore size distributes more widely. Some large pores appear and the mean pore diameter increases by 2 to 3 times. There is little pore connectivity before acid leaching, while the pore connectivity in-creases significantly after acid leaching, being inhomogeneous in three different directions. The fractal dimension of pores also increa-ses after acid leaching, and the porosity and the mean pore diameter grows exponentially with the fractal dimension. 3-D image analy-sis is a powerful technique to quantitatively characterize the micro-scale pore structure of ore particles during acid leaching, so it facili-tates to disclosure the evolution laws of pore structure.